It’s very important to watch what you eat. You are eating for two—which doesn’t mean that you eat more (so say goodbye to that second slice of cake), but that you eat smart. You are your baby’s only source of nutrients, and you need the proper balance of proteins, vitamins, minerals, fiber and carbohydrates.

That being said, most prenatal dieticians strongly advise against adhering to a strict no-carb diet. Without sufficient carbs, your body will produce a by-product called ketones during your blood stream, which can put your baby at risk for brain damage.

But what about low carb diets? Aside from the risk of mental retardation, there are some aspects of low carb diets that can worsen the discomforts of pregnancy. For example, low carb diets tend to have low levels of dietary fiber, which exacerbate the constipation that many pregnant moms suffer because of the required iron supplements. Also, most prenatal dieticians recommend taking a lot of fruit because of its rich vitamin content, but most of the items you’ll find in a typical shake are banned by Atkins and South Beach because of the sugars.

But some doctors may recommend taking modified low-carb diets, especially if you are obese, suffer from gestational diabetes or low blood sugar. All three conditions have been proven to have adverse affects on the baby (including prematurity, birth defects, and early rupture of the membranes) so losing weight or controlling intake may actually be the best thing for your baby.

If you are asked to go on a low-carb diet during pregnancy, you will probably be told to go on the maintenance phase of the Atkins Diet, or the second phase of the South Beach Diet. Here, you are allowed a controlled number of carbohydrates, usually from whole grains and fruits, while minimizing white bread, white rice, and pasta. That is fine, as you are still giving your baby the adequate nutrients, while removing processed foods.

If you are not allowed to go low-carb, but still need to control your weight, there are some options open to you. First of all, eat small but frequent meals. If you want a snack, instead of taking junk food or processed meats (which have a lot of calories, but significantly less nutrients), take salads, fruits, nuts and crackers. Choose lean cuts of meat, and minimize salt and rich sauces during cooking. And while you do need carbohydrates, take in moderation. One plate of pasta is good, three servings of it smothered in white sauce is not.

But the most important thing to remember is that before you go on any diet during pregnancy consult your obstetrician-gynaecologist. She or he can properly determine the best course of action given your particular medical history and the condition of your baby. Do not go on any weight management program without the advice and the approval of your doctor. Whether it’s low carb or Zone or the Mediterranean Diet, the point is that there is a proven link between prenatal nutrition and the baby’s health. Complications can include low birth weight, birth defects, and early delivery.